Microsoft detects a DDoS attack of 3.6 billion packets per second, determining it to be an attack by 'Aisuru,' which hacks more than 500,000 routers and surveillance cameras to build a large-scale botnet

Microsoft has announced that it has detected the largest DDoS attack ever recorded, reaching 15.72 Tbps, or 3.64 billion packets per second.

Defending the cloud: Azure neutralized a record-breaking 15 Tbps DDoS attack | Microsoft Community Hub
https://techcommunity.microsoft.com/blog/azureinfrastructureblog/defending-the-cloud-azure-neutralized-a-record-breaking-15-tbps-ddos-attack/4470422

Microsoft detected a 15.72 Tbps (3.64 billion packets per second) DDoS attack targeted at a single endpoint in Australia on October 24, 2025. The attack was identified as being carried out by a large botnet known as 'Aisuru.'

Aisuru is a botnet built from hacked routers and IoT devices around the world. Attackers are believed to have taken control of servers that distribute firmware updates for IoT devices such as routers and surveillance cameras, and by injecting malicious code into the firmware, they have created a network of hundreds of thousands of devices for DDoS attacks.

The source of the attack power of the world's largest and most destructive botnet 'Aisuru' is 300,000 hacked IoT devices - GIGAZINE

According to Microsoft, the attack was carried out by more than 500,000 devices, but was mitigated by Azure's DDoS protection, and affected users continued to receive uninterrupted service.

Microsoft points out that 'the scale of DDoS attacks continues to grow as internet speeds and IoT device performance improve,' and recommends implementing DDoS attack countermeasures and conducting attack simulations to identify potential issues.